Metal oxide-based undercoat layers are known for use in imaging members. Metal oxide containing undercoat layers provide the functions of blocking holes from metal substrate injection and unidirectional conduction of electrons from a charge generation layer to the metal substrate. The unidirectional conduction of electrons can be achieved by n-type semiconductors particles, such as certain metal oxides.
Metal oxides, such as titanium dioxide (TiO2), can have lower than desired conductivity for undercoat layer applications. Further, it is known that the conductivity of TiO2 can be humidity dependent, so that conductivity of the TiO2 particles in potentially reduced in dry environments. Low conductivity of metal oxides can cause problems, such as ghosting, when the metal oxides are employed in the undercoat layer of an imaging member.
In an attempt to solve such problems, techniques for increasing conductivity of TiO2 have been explored. For example, TiO2 has been surface treated with sodium metaphosphate to enhance conductivity.
Novel methods for increasing the conductivity of metal oxide particles and/or enhancing conductivity of metal oxide particles in less humid environments would be a welcome addition to the art.